This is a 3D action game called knockoff (KO) I've written in C++ using OpenGL. I've been working on it since late June 2003 and its now pretty much complete. I wrote all the code, and did all the art and modeling myself (hence the simple "programmer art" style), but its come together pretty nicely anyway (music was done by a friend of mine). In true cartoon style you have to knock your opponents off the floating platforms any way you can. At the moment its up to 8 players, but only 2 can be human (fitting more than 2 people on a keyboard isn't practical), but I'm working on a networked version so hopefully soon you'll have 8 player deathmatch!

KO runs with over 60fps on my GeForce2 at home and over 200fps on the GeForce4's at my uni. I use no OpenGL extensions (its all done in software), you can turn off almost all features to speed things up, and run it in a mini window if you want so I think it'll run on almost anything with a 3D card (if someone has some old hardware they'd like to test it on I've be interested to see what the minimum specs are).

Current Features include:

Cell Shading

Stencil Buffer Shadows

FMod game sound including an MP3 player

Demo recording + playback

Screen shots (can be used with demo playback to output at 30fps to make game movies)

AI for up to 8 players

Lens flares (not because they help, just because I was board one night)

full quake style console

6 game types (including Deathmatch, CTF and King of the Hill)

10 maps (some mod specific)

6 characters

5 weapons

4 powerups

KO is open source so for anyone who's interested you can get it from my site http://www.kaysik.net. Its cross platform and runs on linux and windows (and theoretically mac, but thats never been tested).